Thx for sharing. I am running a 2.9 whipple on the wife's L86 (6.2l) truck. I am very tempted to turn up the boost, but its a tow rig as well as her daily...so resisting the urge for now. Have you/other tuners been able to connect the dots on what is causing these LT1/L86 pistons to pop when boosted: too aggressive tune, bad gas, aggressive use, etc.? Again, thks for posting this...win/win for everybody, tuners/builders get more $ for builds & satisfied customers and customers get better infor re: risk/blue print for increased safety and reliability...

We push the 6.2 trucks to the same 600hp as the LT1. So far no problems. The ring gaps are very tight on these engines. Thats what we think causes this to happen.

Quote:

Originally Posted by Earl H

Thx for sharing. I am running a 2.9 whipple on the wife's L86 (6.2l) truck. I am very tempted to turn up the boost, but its a tow rig as well as her daily...so resisting the urge for now. Have you/other tuners been able to connect the dots on what is causing these LT1/L86 pistons to pop when boosted: too aggressive tune, bad gas, aggressive use, etc.? Again, thks for posting this...win/win for everybody, tuners/builders get more $ for builds & satisfied customers and customers get better infor re: risk/blue print for increased safety and reliability...

We push the 6.2 trucks to the same 600hp as the LT1. So far no problems. The ring gaps are very tight on these engines. Thats what we think causes this to happen.

Yep, this is correct. The excess heat causes the rings to expand further and causes the ring ends to touch and then boom. Bye bye ringlands. If you boost it, replace the pistons as mentioned. And go a little bigger than stock on the ring end gap. I personally went with .022” for top ring and .025 for the second/scraper ring. I run 15 psi of boost.

I had my ringland fail on cylinder 8. My car drove and ran as it did normally. I didn't even know, thats the worst thing about having it fail.

Only reason i caught it, is because i knew engine was living on borrowed time and i did leak down test when i noticed more oil in catch can and small small misfire at 50mph.. I bet you i drove 300miles with broken ringland.. ( i am guessing i broke it at track )

Even when we do a comp test. Sometimes it won't even show a hurt cylinder. If you don't run a catch can it would blow oil out of the froont seal.

Quote:

Originally Posted by Osman

I had my ringland fail on cylinder 8. My car drove and ran as it did normally. I didn't even know, thats the worst thing about having it fail.

Only reason i caught it, is because i knew engine was living on borrowed time and i did leak down test when i noticed more oil in catch can and small small misfire at 50mph.. I bet you i drove 300miles with broken ringland.. ( i am guessing i broke it at track )